Ultrastructure of the pneumatophores of the mangrove A vicennia marina

Pneumatophores of Avicennia marina (Forssk.) Vierh. were studied by scanning electron microscopy (SEM) in order to relate their ultrastructure to their function as air conduits. The path of air from the atmosphere through the lenticel into the aerenchyma and then to the horizontal root is described. Different states of the lenticels were observed (closed, partially opened, fully opened), and are suggested as developmental stages of the lenticel. The nature of the complementary cells and their role in the aeration function of the lenticel are characterized. Die pneumatofore van Avicennia marina (Forsh.) Vierh. is deur skandeerelektronmikroskopie bestudeer om die verband tussen die ultrastruktuur en hulle funksie as lugweë vas te stel. Die pad van lug vanaf die atmosfeer deur die lentisel na die aerenchiemweefsel en daarna na die horisontale wortel word beskryf. Verskillende toestande van die lentiselle (geslote, gedeeltelik oop en volledig oop), wat waarskynlik ontwikkelingstadia van die lentisel is, is waargeneem. Die aard van die komplementêre selle en hulle rol in die belugtingsfunksie van die lentisel word gekarakteriseer.